Which of the following affects the transition temperature (Tm) of membranes?
Phase transition of lipid bilayers from lamellar gel L beta where acyl chains fully extended ordered tight orthorhombic packing low mobility to liquid crystalline L alpha where chains disordered gauche isomers high mobility monitored by differential scanning calorimetry DSC exhibiting endothermic peak at Tm and by fluorescence anisotropy probes DPH TMA-DPH showing sharp decrease. Factors affecting Tm: chain length longer sixteen to eighteen carbons increases van der Waals interactions raising Tm dipalmitoyl phosphatidylcholine sixteen zero Tm forty one degrees centigrade distearoyl eighteen ze
Ref: McElhaney, Lipid Phase Transition and Chain Length Effect, Biochim Biophys Acta 1984.
